In the field of display technology, there is an increasingly high demand, from a user, for confidentiality of a liquid crystal display device upon displaying information. In a related art, the confidentiality of the liquid crystal display device may be realized by arranging a polarizer (such as a lower polarizer) on a liquid crystal panel of the liquid crystal display device, and integrating an upper polarizer onto a pair of specific-purpose spectacles. To be specific, in the case of using the liquid crystal display device with the lower polarizer to display, a ray of light of a backlight passes through a liquid crystal layer in the liquid crystal panel after being polarized by the lower polarizer, and then emits from the liquid crystal panel. What an observer who does not wear the pair of specific-purpose spectacles with the upper polarizer will see may be an entire white display area of the liquid crystal panel of the liquid crystal device. That is, said observer cannot see any effective image information, thereby improving the confidentiality of the liquid crystal display device upon displaying. However, in a spectacle-type peep-proof device, due to the polarizer, a brightness of the display device is reduced and it is not convenient for a user to wear spectacles.